selftests/bpf: Replace extract_build_id with read_build_id

Replacing extract_build_id with read_build_id that parses out
build id directly from elf without using readelf tool.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230331093157.1749137-4-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
4 files changed